Battery flat after one week parked
 

I left my F650GS twin for a week and came back to find a flat battery. Just before this I had had an annual service with BMW Park Lane so I called them and was informed that this was a normal enough period for the battery to discharge. They said a new battery might do 2 weeks but mine at 2.5 years old, one week was par for the course. Can anyone confirm? Seems mighty short to me. I have to add that the alarm was on (although it is supposed to sleep and then switch off to avoid this issue) and I had a GPS cable (not unit) plugged into the accessory socket (again, theoretically not a problem as the socket is supposed to switch off 15 mins after ignition off)

I am heading off for a year around South America in a few months time and might well have periods where I don't ride for a week or more - so should I carry a solar charger? I am thinking of getting one for home (no power socket availability where I keep the bike in my front garden)

Or does it sound like my battery needs replacing? BMW Park Lane said it just passed their tests...

Hi Goo, I would change the battery before setting of to southern climes. If you travel like I do which means stopping and starting a minimum of 15-20 times a day, pic, food, pea stops and giving your back a break, the battery gets a real hammering and having just taken a magnificent pic of the hands in the middle of the Atacama desert, being greeted with only a click when you engage the propulsion unit energising sequencer can spoil you whole day. As regards the alarm, I stopped using the alarm on my 1200GS except for on short stops in UK crime ridden towns and cities using it when the bike was parked up for 2 days just flattened the battery. Buy an alarmed disc lock and if that flattens your battery you really do have problems. I'm off to S. America myself in about 6 weeks, might see you there. Ride safe.

Interesting.
Thought BMW had eliminated that "sickness" since the /7 series...

Odyssey batteries keep the charging far better than standad acid batteries.

Still, in 1-2 weeks?!... just as it were with the /7 standard 18-20A alternator and prone to be shorted diod-board...

Happens when there is something pulling/using current, like a bike-alarm, /7 diod-board, bad wires, etc.

Good idea to bring a solar-cell-charger!
Look at options with flexible solar-cells to cover the topbox with - I think that might be a good idea/solution :)

Solar power .....
One has to admire an optimist Albert :Beach:
cough cough

I've found that on average a motorcycle battery only lasts me maybe 2 or 3 years - and I've found that they can turn from good to bad at the drop of a hat. They need regular replacement just like other consumable parts.

Motorbike batteries are quite small and can't withstand multiple deep discharges, so it's a good idea to connect up a trickle charger from time to time to keep them topped up and extend the life of the battery. Otherwise the sulphur molecules in the battery acid that are not reactivated instead start to coat the lead plates.

I have an F650GS twin which is coming up for 2 years old. The battery isn't particularly accessible so I wired in a connector coming out near the headstock to make the recharging easier which I do every two weeks. I should really do this more regularly but like you the bike is outside the house, so I have to run a long cable over the garden. I'm finding that it currently takes a couple of hours to bring the battery to full charge, so it looks as if my battery will need replacing before too long. As bclarke says above, batteries go from OK-ish to buggared overnight.

Best thing for your trip is to (1) replace the battery beforehand, and (2) take a multimeter and check the battery charge every few days (again, wiring in a connector will help make this easier). A 12v battery should show around 14v when fully charged. Once it gets below 12.5v sulphation starts in ernest. The good news is that getting a suitable replacement battery on the road isn't as difficult as I would have thought, though getting one to fit neatly can be more of a problem.

Several times I've been with people when their battery has discharged so much when riding offroad that it won't start. The cause is normally stop/start riding, especially with auxillary lighting, heated grips and so on, but also forgetting to turn the ignition (and therefore headlight) off when the engine isn't running.

One of the really nice things about the F650GS twin is that when the engine stops running the headlight switches itself off automatically (marvels of CanBUS) even when the ignition is still on, so you won't get so much of a problem in this area.

Probably another in a long line of stupid questions.. :blushing: but do people generally carry a charger when on long tours?

I never have. Push-starting pillions do weigh more, but I have found them far more versatile. ;)

On a long trip you don't need a charger, so long as

1. you start with a decent battery in the first place
2. you are riding fair distances every day
3. you are not constantly stopping/starting
4. and not using tons of accessories, especially extra lights and heated jacket/grips

Hmm. Well I will have a new battery and I'm not planning on tons of accessories but I tend to amble, stop a fair bit and maybe not ride for a day or two here and there. One time I stored my bike for a month in Thailand. It had an ancient battery and was started fine when I came back to it..

I'm quite taken with the idea of a Lithium battery though and it sounds like they hold their charge much better than Lead-Acid. I guess I will just have to test the battery out a bit before I go and see how much confidence it inspires.

Your £80 an hour BMW mechanic is telling you porkies or at the very least, speaking out of ignorance. A healthy battery WILL NOT spontaneously self discharge on two days. It is simply not capable of doing this.

No matter how deep the shag pile carpet in these fancy dealers gets the old "they all do that mister" attitude persists - lol.

If your bike is still under warranty take it back and TELL them (don't ask) to sort it out and provide you will a detailed report from the auto electrical technician listing the checks they did. Insist on this check list. Don't accept "no fault found" from these bozos.

If you bike is out of warranty take it to a reputable auto electrician. After they have finished laughing at the £80 an hour Park Lane BMW technician they will test your battery then test stator output, test loads in all states i.e. ignition on/off alarm on/off and any other condition they wish, identifying and quantifying electrical loads and quality of grounds, connectors, terminations etc. From this they will give you a report on what is happening on your electrical system and what you need to do to give you the security you require on your trip. The fixes are often very simple and cost little or nothing.

When they have done this and solved your problem take their report together with your newly fixed BMW to BMW Park Lane and ask them politely to settle the bill from the auto electrician doh

Motorbike electrics are crap and totally inadequate for out of the way riding. If you are not sparky take your bike to a sparky before the big trip and ask for a check up and their advice.

Include a functioning regulator/rectifier in your spares stash!

I have a question: can you take the battery out of your BMW and still bump start it?

Hi Fastship

According to Bertrand on another of my threads, you wouldn't be able to bump start without a battery as the fuel system needs some volts to pressurise. Guess this is a downside of Fuel Injection.

The battery didn't discharge in 2 days, it was 8 in fact. Still very short mind you. My guess is that it was the alarm system, reading between the lines of a few comments I've had. This is despite the manual saying that it goes into sleep mode and cuts off after a few days to avoid this exact problem. Maybe my battery is a bit old and then the alarm pushed it over the edge on this occasion. I think I'm going to need a new battery for my trip anyway, so I'm going to get a Lithium one and monitor its' volts and also carry jump leads.

I'm going to call up Park Lane tomorrow and grill them a bit more deeply based on everyone's comments...

Caution on the lithium batteries ... they "hold" charge better, but generally they have less charge to hold. They deliver tremendous starting power- much more than a conventional battery. I have just swapped my 3kg, 10AH odyssey to a 0.5 kg lithium battery. It starts like a dream. It takes years to self discharge ... BUT the amount of power is is capable of storing is a lot less than the equivalent Lead Acid battery.

i.e. if you are not using ANY current while parked up, the lithium battery will survive better, as it will discharge much less and still give you that massive starting power whenever you turn to it. But if you have an alarm on for a week, without riding the bike, a lithium battery will discharge faster, because it doesnt store as much power as a Lead battery and your alarm will use up the charge in a Li battery faster than it would on a larger heavier Pb battery.

So as for what is better, it depends on how you use it.

Isn't it just about the Ampere-hours? ie if you have a Lead-Acid battery and a Lithium battery both rated 14Ah, they should discharge at the rate rate - 1 amp for 14 hours or 0.5 amps for 28 hours etc.

Or maybe I'm missing something?

...I did mean as a back-up system for charging whilst parked, not as primary energy sorce for driving...
:innocent:

To use a solarcell as substitute for gas/petrol, now -that- would be a bit optimistic, still there is an annual race across Australia with solarpowered vehicles.
:palm: :taz:



Lets enjoy the techinological development of vehicles.
bier


On the Swedish market, for cars, I know of these two options:
Solcellspanel f�r bilbatteri 17,5 V 1,5 W - Jula Online – Allt för ditt hemmaprojekt!
1.5W... that is too little to make a difference less used over several days...
13W is far better, but far from what is really needed:
Solcellspanel i v�ska 12 V 13 W - Jula Online – Allt för ditt hemmaprojekt!

These are not just plug-in gadgets since they deliver 17V.

Back in the 80:ties I was taught that one should use about 10% of the batterys capacity as charging current - this may well have changed since then though; but is gives a hint of the need.

I find it really odd - it appears modern bikes discharge their batteries its something you hear a lot of all the time - maybe its alarms and all the gizmos people run, maybe they have poor batteries, Other than a Moto guzzi I owned most of my bike including Laverdas, BM airheads, Cagivas and KTM to name a few have been used for everything from daily rides, for commuting and as everyday transport as well as long haul travel bikes never really suffered discharged batteries in storage and very rare has it been when I have not been able to start a bike off the button or the kicker. I have never used these trickle charge gizmos, never ever had an alarm on a bike - that's i think is just asking for trouble and have always done good maintenance on the electrical system ie kept fitting and plugs well cleaned and lubricated with electrical grease, earths kept clean , battery terminals cleaned and greased, once a year seems to keep on top of it all - that includes winter riding - so I think the bike you have must have a leakage to earth through a bad connection, broken wire or something is staying on and agree a good auto electrician should be able to sort the problem. But if it were me I would get rid of the alarm, clean and lubricate every electrical connector, check where you can for possible broken wires or shorts, take your battery off give it a good charge and get a drop test carried out at a local car shop, if that seems ok you may have solved the fault if not the auto electrician is the man to turn to next. I would not be inclined to trust BMW main dealers they are not auto electricians there 'mechanics' are mostly fitters of sorts, cost too much and often have neither the skill or the experience and knowledge of a good auto electrician. Good luck with it though.

Short answer - NO!

It's all to do with the achitecture and chemistry of the each capacitor and some confusion marketing too. The two types of battery you quote are different devices doing the same job so you have to rely on the makers' explanation and specs. to enable an "apples with apples" comparison when making your choice;

Lead-acid makers have used AHr(capacity) ratings as shorthand to indicate cranking ability, rather than a real usable capacity. The lead-acid capacity rating itself is based on a complete discharge at a low discharge rate. Under actual cranking conditions they will deliver considerably less than spec capacity. And because lead-acid batteries begin sulfating when only a small percentage of the capacity has been used, and their internal resistance rises as they are discharged, the actual capacity which can be USED may be as little as 20% of the mfg. rating. Discharge in excess will not only damage the lead-acid battery, it may not allow proper starting as voltage sags.
Shorai LFX are based on a completely different chemistry. Not only do they have less than 1/3 the internal resistance per capacity than do lead-acid, they are also the ultimate "deep-cycle" battery. The internal "completely discharged" capacity of a Shorai LFX is 1/3 the rated "PBeq" capacity. For example, the LFX18 12V series have 6Ah cells internally. But the cells are capable of 90% discharge without damage and while retaining more cranking ability. As such, the USABLE capacity(or "reserve capacity") of an LFX18 12V battery is on or very near par with 18AHr-rated lead acid batteries, while providing superior cranking performance and a vast reduction in weight. The Shorai PBeq AHr (lead-acid equivalent) rating system therefore allows users to compare a very different technology from lead-acid, but on a close apples-to-apples basis when making a choice.

Shorai's explanation. Colebatch is correct, Shorai sell an equivalent 18 Ah equivalent battery which is 6Ah but will give the same or better real world performance as an 18Ah lead/acid battery FOR STARTING. A motorcycle battery is a STARTER battery and purposed to supply the required volts to start to engine and not to do any other task. Also remember, contrary to popular belief starting uses only a tiny amount of the battery's stored energy and is replenished within minutes. It's all the extras attached to the bikes electrical system combined with the inadequate OEM design of the loom R/R and alternator that stresses the battery.

Adventure 950 - Laverda's; now they were real bikes! lol. BMW's "technicians" are only allowed to plug into the CAN bus now. Your bike might be a smouldering puddle of solder but if the computer says "no fault found" then there's nothing wrong with your bike. It's the box ticking "computer says no" syndrome plaguing modern British life :(

Who would be interested in a two battery solution (one exclusively starter, one deep storage) with properly designed alternator, three stage charging and wiring loom?

Um.

So what I understand from this is that the Shorai will be good for starting.

I'm still not sure whether they will be better or worse than Lead-Acid if you left them slowly discharging - whether that is because or a fault/current leak or because you left some device on while parked, e.g. an alarm.

My guess is that my problem was because I left my alarm on despite the manual's insistence that it shouldn't matter.

I've now ordered a Shorai LiFeP04 LFX14A2-BS12 - seduced by the weight saving and lack of maintenance obligations - I guess I will see if it was the right decision...

Thanks to all for their time and insights!